Color correction filters and gels are rated in mireds (micro reciprocal degrees), not Kelvin. Enter the source and target color temperatures to get the mired shift and an approximate gel strength.
How it works
Mired = 10⁶ ÷ K; shift = mired(target) − mired(source). Full CTO ≈ +159, full CTB ≈ −131 mired (typical).
FAQ
Why mireds?
Equal mired steps look like equal color shifts, unlike Kelvin.
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